Merge "Use Gradle instead of Ant" into ub-jack

.gitignore

args4j/build.gradle

build.gradle

build.xml

core-stubs-mini/build.gradle

ddmlib/build.gradle

dexcomparator/build.gradle

dexlib/build.gradle

dx-ref/build.gradle

ecj-tests-lib/build.gradle

ecj/build.gradle

gradle-script/checkstyle.gradle

gradle-script/dependencies.properties

gradle-script/findbugs.gradle

gradle-script/libversions.gradle

gradle-script/versionfile.gradle

gradle.properties

gradle/wrapper/gradle-wrapper.jar

gradle/wrapper/gradle-wrapper.properties

gradlew